Solid-state image pickup apparatus and electronic apparatus

ABSTRACT

Provided is a solid-state image pickup apparatus including a crosstalk suppression mechanism included in each pixel arranged in a pixel array, the crosstalk suppression mechanism of a part of the pixels differing from that of other pixels in an effective area of the pixel array.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/319,686 filed Jun. 30, 2014, the entirety of which is incorporatedherein by reference to the extent permitted by law. This applicationclaims the benefit of Japanese Priority Patent Application JP2013-145817 filed Jul. 11, 2013, the entire contents of which areincorporated herein by reference.

BACKGROUND

The present disclosure relates to a solid-state image pickup apparatusand an electronic apparatus, more particularly, to a solid-state imagepickup apparatus and an electronic apparatus with which a correction ofa pixel signal can be avoided as much as possible and an image planephase difference AF can be executed appropriately.

In recent years, cameras adopt an image plane phase difference AF forboth a model miniaturization and an AF (autofocus) function.

In the image plane phase difference AF, the AF is performed by arranginga plurality of pixels in which left, right, top, and bottom of anopening portion of a photodiode (PD) are partially optically shielded inan angle of view and acquiring a phase difference signal from thosepixels.

Since an AF speed is higher than that of a contrast AF system and thereis no need to mount an AF image pickup device, the image plane phasedifference AF is effective in miniaturizing the camera and loweringcosts.

The image plane phase difference AF pixels (also referred to as phasedifference pixels) have a pixel structure in which about half of the PDon the left and right or at the top and bottom is optically shielded.The phase difference pixels are arranged in a pair (do not always needto be adjacent to each other), and the two phase difference pixelsgenerate a single phase difference signal from different obliqueincidence characteristics thereof (see, for example, Japanese PatentApplication Laid-open No. 2009-157198).

SUMMARY

However, in the image plane phase difference AF of the related art, asensitivity of the phase difference pixels is always lower than that ofnormal pixels, and it has been difficult to use an output signal forimage pickup.

Therefore, for obtaining a pixel signal corresponding to pixel positionsof the phase difference pixels in the related art, it has been necessaryto perform a defect correction.

Further, when a density of the phase difference pixels is raised forraising AF characteristics, there is a fear that a defective pixelstands out or a circuit scale becomes large. Furthermore, sincecrosstalk due to a reflection by a light shield film occurs also innormal pixels adjacent to the phase difference pixels, a crosstalkcorrection has also been necessary.

The present disclosure has been made in view of the circumstances asdescribed above, and thus there is a need for a technique with which apixel signal correction can be avoided as much as possible and an imageplane phase difference AF can be executed appropriately.

According to an embodiment of the present disclosure, there is provideda solid-state image pickup apparatus including a crosstalk suppressionmechanism included in each pixel arranged in a pixel array, thecrosstalk suppression mechanism of a part of the pixels differing fromthat of other pixels in an effective area of the pixel array.

The crosstalk suppression mechanism may be a DTI.

The part of the pixels in the effective area of the pixel array may be aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF, and the DTI around apixel surrounded by the phase difference pixels may be removed.

The part of the pixels in the effective area of the pixel array may be aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF, and the DTI may beprovided only around a pixel surrounded by the phase difference pixels.

The crosstalk suppression mechanism may be realized by adjusting an ionimplantation amount for the pixels arranged in the pixel array.

The part of the pixels in the effective area of the pixel array may be aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF, and an ionimplantation amount for an electronic barrier of a pixel surrounded bythe phase difference pixels may be smaller than that for an electronicbarrier of other pixels.

The part of the pixels in the effective area of the pixel array may be aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF, and an ionimplantation amount for a sensor area of a pixel surrounded by the phasedifference pixels may be smaller than that for an electronic barrier ofother pixels.

The crosstalk suppression mechanism may be an OBB, the part of thepixels in the effective area of the pixel array may be a plurality ofphase difference pixels for obtaining a phase difference signal used inan image plane phase difference AF, and the OBB of a pixel surrounded bythe phase difference pixels may be removed.

The crosstalk suppression mechanism may be a waveguide, the part of thepixels in the effective area of the pixel array may be a plurality ofphase difference pixels for obtaining a phase difference signal used inan image plane phase difference AF, and the waveguide of a pixelsurrounded by the phase difference pixels may be removed.

The crosstalk suppression mechanism may be an on-chip lens, the part ofthe pixels in the effective area of the pixel array may be a pluralityof phase difference pixels for obtaining a phase difference signal usedin an image plane phase difference AF, and the on-chip lens of a pixelsurrounded by the phase difference pixels may be structured such that alight collection property thereof becomes weak.

The crosstalk suppression mechanism may be realized by a color filter,the part of the pixels in the effective area of the pixel array may be aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF, and only the colorfilter of a pixel surrounded by the phase difference pixels may bewhite.

The part of the pixels in the effective area of the pixel array may be aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF, and the color filtersof the same color may be arranged for the phase difference pixels.

The part of the pixels in the effective area of the pixel array may be aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF, and a pixel adjacentto a predetermined pixel in a vertical direction and a pixel adjacent tothe predetermined pixel in a horizontal direction out of the pixels ofthe pixel array arranged in a 2D matrix may be the phase differencepixels.

The part of the pixels in the effective area of the pixel array may be aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF, two pixels adjacentto each other in a vertical direction and two pixels adjacent to eachother in a horizontal direction out of the pixels of the pixel arrayarranged in a 2D matrix may be the phase difference pixels, and the twopixels adjacent to each other in the vertical direction and the twopixels adjacent to each other in the horizontal direction may bearranged in an L shape.

According to another embodiment of the present disclosure, there isprovided an electronic apparatus including a solid-state image pickupapparatus. The solid-state image pickup apparatus includes a crosstalksuppression mechanism included in each pixel arranged in a pixel array,the crosstalk suppression mechanism of a part of the pixels differingfrom that of other pixels in an effective area of the pixel array.

According to the embodiments of the present disclosure, regarding thecrosstalk suppression mechanism included in each pixel arranged in thepixel array, the crosstalk suppression mechanism of a part of the pixelsdiffers from that of other pixels in the effective area of the pixelarray.

According to the embodiments of the present disclosure, it is possibleto avoid a pixel signal correction as much as possible and appropriatelyexecute the image plane phase difference AF.

These and other objects, features and advantages of the presentdisclosure will become more apparent in light of the following detaileddescription of best mode embodiments thereof, as illustrated in theaccompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view showing a structural example of phase differencepixels arranged in a pixel portion of an image sensor used in an imageplane phase difference AF of the related art;

FIG. 2 is a diagram showing a structural example of a pixel portion ofan image sensor to which the present disclosure is applied;

FIG. 3 is a diagram for explaining a crosstalk suppression effect of aDTI;

FIG. 4 is a cross-sectional diagram of the pixel portion of the imagesensor shown in FIG. 2 taken along the line A-A′;

FIG. 5 is a diagram showing another structural example of the pixelportion of the image sensor to which the present disclosure is applied;

FIG. 6 is a cross-sectional diagram of the pixel portion of the imagesensor shown in FIG. 5 taken along the line A-A′;

FIG. 7 is a diagram showing an example of the pixel portion of the imagesensor in a case of obtaining a phase difference signal by a method ofthe related art;

FIG. 8 is a diagram showing another example of the cross-sectionaldiagram of the pixel portion of the image sensor to which the presentdisclosure is applied;

FIG. 9 is a diagram showing another example of the cross-sectionaldiagram of the pixel portion of the image sensor to which the presentdisclosure is applied;

FIG. 10 is a diagram showing another example of the cross-sectionaldiagram of the pixel portion of the image sensor to which the presentdisclosure is applied;

FIG. 11 is a diagram showing another example of the cross-sectionaldiagram of the pixel portion of the image sensor to which the presentdisclosure is applied;

FIG. 12 is a diagram showing another example of the cross-sectionaldiagram of the pixel portion of the image sensor to which the presentdisclosure is applied;

FIG. 13 is a diagram showing another structural example of the pixelportion of the image sensor to which the present disclosure is applied;

FIG. 14 is a cross-sectional diagram of the pixel portion of the imagesensor shown in FIG. 13 taken along the line A-A′;

FIG. 15 is a diagram showing another structural example of the pixelportion of the image sensor to which the present disclosure is applied;

FIG. 16 is a cross-sectional diagram of the pixel portion of the imagesensor shown in FIG. 15 taken along the line A-A′;

FIG. 17 is a diagram showing another structural example of the pixelportion of the image sensor to which the present disclosure is applied;

FIG. 18 is a diagram showing another structural example of the pixelportion of the image sensor to which the present disclosure is applied;

FIG. 19 is a system structural diagram schematically showing asolid-state image pickup apparatus to which the present disclosure isapplied; and

FIG. 20 is a block diagram showing a structural example of thesolid-state image pickup apparatus as an electronic apparatus to whichthe present disclosure is applied.

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present disclosure will be describedwith reference to the drawings.

FIG. 1 is a plan view showing a structural example of phase differencepixels arranged in a pixel portion of an image sensor used in an imageplane phase difference AF (autofocus) of the related art. As shown inFIG. 1, in the pixel portion of the image sensor, a plurality of pixelsillustrated as rectangles in the figure are arranged in a 2D matrix.

Such a pixel portion is structured as a pixel array of the image sensor.Here, a part of the pixels arranged in an effective area of the pixelarray are shown.

As shown in the figure, pixels in which half of an opening portion of aphotodiode (PD) is optically shielded are arranged as phase differencepixels. The phase difference pixels are arranged in a pair (do notalways need to be adjacent to each other), and the two phase differencepixels generate a single phase difference signal based on differentoblique incidence characteristics thereof.

Here, the phase difference signal refers to one pixel signal output bythe two phase difference pixels.

For example, a focal point detection area is set in an effective pixelarea of a light reception area in the image sensor. In the image planephase difference AF, a focus position of a lens is detected based on thephase difference signal output by the phase difference pixels in thefocal point detection area.

At this time, for obtaining a phase difference signal used in detectingthe focus position, the phase difference pixels are structured to havedifferent oblique incidence characteristics.

In the example of FIG. 1, a phase difference pixel P1 and a phasedifference pixel P2 are provided. A right half of the opening portion ofthe phase difference pixel P1 in the figure is blackened, and byproviding a light shield film at this portion, light is shielded.Moreover, a left half of the opening portion of the phase differencepixel P2 in the figure is blackened, and by providing a light shieldfilm at this portion, light is shielded.

In the case of the structure shown in FIG. 1, since the phase differencepixel P1 is optically shielded at the right half of the opening portion,a light reception sensitivity with respect to light that enters from anupper left-hand direction is high while the light reception sensitivitywith respect to light that enters from an upper right-hand direction islow. In contrast, since the phase difference pixel P2 is opticallyshielded at the left half of the opening portion, a light receptionsensitivity with respect to light that enters from an upper right-handdirection is high while the light reception sensitivity with respect tolight that enters from an upper left-hand direction is low.

As described above, in the case of the structure shown in FIG. 1, thephase difference pixel P1 and the phase difference pixel P2 arestructured to have different oblique incidence characteristics.

It should be noted that although the two phase difference pixels arearranged in the lateral direction in the figure, the two phasedifference pixels are also arranged in the longitudinal direction in thefigure in actuality. In other words, the phase difference pixel P1 andthe phase difference pixel P2 are phase difference pixels for obtaininga phase difference signal in the lateral direction (horizontaldirection), and phase difference pixels for obtaining a phase differencesignal in the longitudinal direction (vertical direction) are alsoprovided.

However, since half of the opening portion of the phase differencepixels is optically shielded when structuring the phase differencepixels as shown in FIG. 1, a value of a pixel signal output from thephase difference pixels becomes smaller than that of a pixel signaloutput from other pixels in the effective area (referred to as normalpixels) even in the case of pixel signals corresponding to the samelight reception amount.

Therefore, in the image plane phase difference AF of the related art,the phase difference pixels have been handled as defective pixels, anddefect correction processing of predictively generating a pixel signalof phase difference pixels has been carried out based on a pixel signalof pixels adjacent to the phase difference pixels, for example.

Further, when a light shield film is provided as shown in FIG. 1, lightis reflected by the light shield film, and thus the reflected light mayenter peripheral pixels. Therefore, in the image plane phase differenceAF of the related art, crosstalk correction processing for removingcrosstalk components due to an incorporation of light reflected by thelight shield film has been carried out on a pixel signal output frompixels adjacent to the phase difference pixels, for example.

In this regard, the present disclosure aims at enabling a correction ofa pixel signal to be avoided as much as possible and the image planephase difference AF to be executed appropriately.

FIG. 2 is a diagram showing a structural example of a pixel portion ofan image sensor to which the present disclosure is applied. As shown inthe figure, a plurality of pixels illustrated as rectangles in thefigure are arranged in the pixel portion of the image sensor in a 2Dmatrix.

Such a pixel portion is structured as a pixel array of the image sensor.Here, a part of the pixels arranged in the effective area of the pixelarray are shown.

In this example, a DTI (Deep Trench Isolation) is adopted for the imagesensor. The DTI is a technique of forming a trench between pixels andembedding an oxide film therein to thus suppress an incorporation ofcharges among the pixels and the like. In other words, the DTI isadopted as a crosstalk suppression mechanism for suppressing crosstalkthat occurs due to incident light entering adjacent pixels, anincorporation of a pixel signal of adjacent pixels, and the like in theimage sensor.

In FIG. 2, black frame borders drawn along the rectangles indicate theDTI. In this example, a pixel PL and pixel PR and a pixel PA and pixelPB are the phase difference pixels. Specifically, a lateral phasedifference signal is obtained by the phase difference pixel PL and thephase difference pixel PR, and a longitudinal phase difference signal isobtained by the phase difference pixel PA and the phase difference pixelPB.

Although the DTI is arranged on 4 sides of the rectangular pixel inprinciple in the structure shown in FIG. 2, the DTI is not exceptionallyarranged on 4 sides of a pixel PC arranged at the center of the 4 phasedifference pixels, that is, the phase difference pixel PL, the phasedifference pixel PR, the phase difference pixel PA, and the phasedifference pixel PB.

FIG. 3 is a diagram for explaining a crosstalk suppression effect of theDTI. In the figure, the abscissa axis represents a light incident angle,and the ordinate axis represents a crosstalk amount. The curve 31represents a change of the crosstalk amount accompanying a change of thelight incident angle of the image sensor in which a DTI is not provided,and the curve 32 represents a change of the crosstalk amountaccompanying a change of the light incident angle of the image sensor inwhich a DTI is provided.

As shown in FIG. 3, the curve 32 shows that the change of the crosstalkamount accompanying the change of the light incident angle is moregradual than the curve 31. In other words, in the image sensor in whicha DTI is not provided, (an absolute value of) the light incident anglebecomes large, and when light enters obliquely, the crosstalk amountincreases prominently. In contrast, in the image sensor in which a DTIis provided, it can be seen that the crosstalk amount does not increasemuch even when light enters obliquely.

In the present disclosure, crosstalk that occurs due to incident lightentering adjacent pixels, an incorporation of a pixel signal of adjacentpixels, and the like is used in place of the oblique incidencecharacteristics of the phase difference pixels. Specifically, in thepresent disclosure, the phase difference pixels are structured to havedifferent crosstalk amounts for obtaining a phase difference signal usedin detecting a focus position.

FIG. 4 is a cross-sectional diagram of the pixel portion of the imagesensor shown in FIG. 2 taken along the line A-A′ and is a diagram forexplaining a difference in the crosstalk amounts of the phase differencepixels shown in FIG. 2.

FIG. 4 shows a cross-sectional diagram of the phase difference pixel PL,the phase difference pixel PR, the pixel PC, and a pixel PR1 located onthe right-hand side of the phase difference pixel PR in FIG. 2.

As shown in FIG. 4, an on-chip lens (OCL) and a color filter (CF) arearranged in each pixel, and an OBB for preventing stray light isprovided under the CF. Here, a Bayer arrangement is adopted for thepixel portion, and the pixels respectively correspond to colorcomponents of red (R), green (Gr, Gb), and blue (B). For example, a redCF is arranged in the phase difference pixel PL, a green CF is arrangedin the pixel PC, a red CF is arranged in the phase difference pixel PR,and a green CF is arranged in the pixel PR1. Light that has passedthrough the OCLs and CFs enters the sensor areas of the sensors.

It is assumed that light whose direction from the upper right to thelower left becomes dominant in FIG. 4 is entering the pixel portion. Inthis case, for example, regarding the pixel corresponding to the greencolor component, an optical component to be absorbed by the sensor areaof the pixel itself and an optical component that is to be incorporatedinto the sensor area of the pixel on the immediate left, thatcorresponds to the red color component, enter that pixel. Here, theoptical component to be absorbed by the sensor area of the pixel itselfis represented by Gr_(−Gr), and the optical component to be incorporatedinto the sensor area of the pixel on the immediate left, thatcorresponds to the red color component, is represented by R_(−Gr).

Further, for example, regarding the pixel corresponding to the red colorcomponent, an optical component to be absorbed by the sensor area of thepixel itself and an optical component that is to be incorporated intothe sensor area of the pixel on the immediate left, that corresponds tothe green color component, enter that pixel. Here, the optical componentto be absorbed by the sensor area of the pixel itself is represented byR_(−R), and the optical component to be incorporated into the sensorarea of the pixel on the immediate left, that corresponds to the greencolor component, is represented by G_(−R).

In the case of the example shown in FIG. 4, regarding the pixel PR1corresponding to the green color component, the optical componentGr_(−Gr) to be absorbed by the sensor area 52-4 of the pixel itself andthe optical component R_(−Gr) to be incorporated into the sensor area ofthe pixel on the immediate left, that corresponds to the red colorcomponent, enter that pixel. However, the component R_(−Gr) issuppressed from entering by the DTI 51-2 and is thus absorbed by thesensor area 52-4 of the pixel itself.

Moreover, regarding the phase difference pixel PR corresponding to thered color component, the optical component R_(−R) to be absorbed by thesensor area 52-3 of the pixel itself and the optical component Gr_(−R)to be incorporated into the sensor area 52-2 of the pixel on theimmediate left, that corresponds to the green color component, enterthat pixel. In this case, since the DTI is not provided between thephase difference pixel PR and the pixel PC, the component Gr_(−R) entersthe sensor area 52-2 of the pixel PC as it is.

Furthermore, regarding the pixel PC corresponding to the green colorcomponent, the optical component Gr_(−Gr) to be absorbed by the sensorarea 52-2 of the pixel itself and the optical component R_(−Gr) to beincorporated into the sensor area 52-1 of the pixel on the immediateleft, that corresponds to the red color component, enter that pixel.

In this case, since the DTI is not provided between the phase differencepixel PL and the pixel PC, the component Gr_(−R) enters the sensor area52-1 of the phase difference pixel PL as it is.

Furthermore, regarding the phase difference pixel PL corresponding tothe red color component, the optical component R_(−R) to be absorbed bythe sensor area 52-1 of the pixel itself and the optical componentG_(−R) to be incorporated into the sensor area 52-1 of the pixel on theimmediate left, that corresponds to the green color component, enterthat pixel. However, the component Gr_(−R) is suppressed from enteringby the DTI 51-3 and is thus absorbed by the sensor area 52-1 of thepixel itself.

As a result, in the sensor area 52-3 of the phase difference pixel PR,only the optical component R_(−R) is absorbed and photoelectricallyconverted, and in the sensor area 52-1 of the phase difference pixel PL,the optical component R_(−R) and the component Gr_(−R) that has beenincorporated from the pixel PC is absorbed and photoelectricallyconverted in addition to the component G_(−R). Consequently, in the casewhere light whose direction from the upper right to the lower leftbecomes dominant is entering the pixel portion, the value of the pixelsignal output from the phase difference pixel PR becomes small, and thevalue of the pixel signal output from the phase difference pixel PLbecomes large.

It should be noted that when light whose direction from the upper leftto the lower right becomes dominant is entering the pixel portion, thevalue of the pixel signal output from the phase difference pixel PRbecomes large, and the value of the pixel signal output from the phasedifference pixel PL becomes small in contradiction to the example above.

In other words, while the phase difference pixel PL has a high lightreception sensitivity with respect to light that enters from the upperright, it has a low light reception sensitivity with respect to lightthat enters from the upper left. In contrast, while the phase differencepixel PR has a high light reception sensitivity with respect to lightthat enters from the upper left, it has a low light receptionsensitivity with respect to light that enters from the upper right. Thisis because the crosstalk amounts caused by incident light enteringadjacent pixels, an incorporation of a pixel signal from adjacentpixels, and the like at a time light that has entered from the samedirection is received differ for the phase difference pixel PL and thephase difference pixel PR.

Moreover, as shown in FIG. 2, since the DTI is not provided between thephase difference pixel PA and the pixel PC and also between the phasedifference pixel PB and the pixel PC, the phase difference pixel PA andthe phase difference pixel PB also have different light receptionsensitivities.

As described above, according to the present disclosure, a phasedifference signal can be obtained without providing a light shield film.In other words, since the light shield film is not provided in the phasedifference pixels, the value of the pixel signal output from the phasedifference pixels does not become extremely smaller than that of thepixel signal output from normal pixels. Therefore, in the presentdisclosure, there is no need to handle the phase difference pixels asdefective pixels and carry out the defect correction processing.

Further, according to the present disclosure, there is also no need tocarry out the crosstalk correction processing for removing crosstalkcomponents due to entering of light reflected by the light shield film.

The structure in which the DTI is arranged on 4 sides of a rectangularpixel in principle and the DTI is not arranged exceptionally on 4 sidesof the pixel PC arranged at the center of the 4 phase difference pixelshas been described with reference to FIG. 2. However, a structure inwhich the DTI is not arranged on 4 sides of a rectangular pixel inprinciple and the DTI is arranged exceptionally on 4 sides of the pixelPC arranged at the center of the 4 phase difference pixels may be usedinstead.

FIG. 5 is a diagram showing another structural example of the pixelportion of the image sensor to which the present disclosure is applied.Such a pixel portion is structured as a pixel array of the image sensor.Here, a part of the pixels arranged in the effective area of the pixelarray are shown.

In this example, the DTI is not arranged on 4 sides of a rectangularpixel in principle, and the DTI is arranged exceptionally on 4 sides ofthe pixel PC arranged at the center of the 4 phase difference pixels. Itshould be noted that in FIG. 5, the black frame border drawn along therectangle indicates the DTI.

FIG. 6 is a cross-sectional diagram of the pixel portion of the imagesensor shown in FIG. 5 taken along the line A-A′ and is a diagram forexplaining a difference between the crosstalk amounts of the phasedifference pixels shown in FIG. 5.

In the case of FIG. 6, the Bayer arrangement is adopted for the pixelportion as in the case of FIG. 4, and the pixels respectively correspondto the color components of red (R), green (Gr, Gb), and blue (B). Forexample, a red CF is arranged in the phase difference pixel PL, a greenCF is arranged in the pixel PC, a red CF is arranged in the phasedifference pixel PR, and a green CF is arranged in the pixel PR1.

It is assumed that light whose direction from the upper right to thelower left becomes dominant in FIG. 6 is entering the pixel portion.

In the case of the example shown in FIG. 6, although the opticalcomponent R_(−Gr) to be incorporated into the sensor area 52-3 of thephase difference pixel PR on the immediate left, that corresponds to thered color component, enters the pixel PR1 corresponding to the greencolor component, since the DTI is not provided between the pixel PR1 andthe phase difference pixel PR, the component R_(−Gr) is incorporatedinto the sensor area 52-3 of the phase difference pixel PR as it is.

Further, in the case of the example shown in FIG. 6, regarding the phasedifference pixel PR corresponding to the red color component, theoptical component R_(−R) to be absorbed by the sensor area 52-3 of thepixel itself and the optical component Gr_(−R) to be incorporated intothe sensor area 52-2 of the pixel PC on the immediate left, thatcorresponds to the green color component, enter that pixel. However, thecomponent Gr_(−R) is suppressed from entering by the DTI 51-11 and isthus absorbed by the sensor area 52-3 of the pixel itself.

Furthermore, in the case of the example shown in FIG. 6, regarding thepixel PC corresponding to the green color component, the opticalcomponent Gr_(−Gr) to be absorbed by the sensor area 52-2 of the pixelitself and the optical component R_(−Gr) to be incorporated into thesensor area 52-1 of the phase difference pixel PL on the immediate left,that corresponds to the red color component, enter that pixel. However,the component R_(−Gr) is suppressed from entering by the DTI 51-12 andis thus absorbed by the sensor area 52-2 of the pixel itself.

Furthermore, in the case of the example shown in FIG. 6, regarding thephase difference pixel PL corresponding to the red color component, theoptical component R_(−R) to be absorbed by the sensor area 52-1 of thepixel itself and the optical component G_(−R) to be incorporated intothe sensor area of the pixel on the immediate left, that corresponds tothe green color component, enter that pixel. In this case, since the DTIis not provided between the phase difference pixel PL and the pixel onthe immediate left, the component Gr_(−R) enters the sensor area of thepixel on the immediate left as it is.

As a result, in the sensor area 52-1 of the phase difference pixel PL,only the optical component R_(−R) is absorbed and photoelectricallyconverted, and in the sensor area 52-3 of the phase difference pixel PR,the optical component R_(−R) and the component Gr_(−R) that has beenincorporated from the pixel PR1 is absorbed and photoelectricallyconverted in addition to the component G_(−R). Consequently, in the casewhere light whose direction from the upper right to the lower leftbecomes dominant is entering the pixel portion, the value of the pixelsignal output from the phase difference pixel PL becomes small, and thevalue of the pixel signal output from the phase difference pixel PRbecomes large.

It should be noted that when light whose direction from the upper leftto the lower right becomes dominant is entering the pixel portion, thevalue of the pixel signal output from the phase difference pixel PLbecomes large, and the value of the pixel signal output from the phasedifference pixel PR becomes small in contradiction to the example above.

In other words, in the case of the example shown in FIG. 6, while thephase difference pixel PR has a high light reception sensitivity withrespect to light that enters from the upper right, it has a low lightreception sensitivity with respect to light that enters from the upperleft. In contrast, while the phase difference pixel PL has a high lightreception sensitivity with respect to light that enters from the upperleft, it has a low light reception sensitivity with respect to lightthat enters from the upper right. This is because the crosstalk amountscaused by incident light entering adjacent pixels, an incorporation of apixel signal from adjacent pixels, and the like at a time light that hasentered from the same direction is received differ for the phasedifference pixel PL and the phase difference pixel PR.

Moreover, as shown in FIG. 5, since the DTI is provided between thephase difference pixel PA and the pixel PC and also between the phasedifference pixel PB and the pixel PC, the phase difference pixel PA andthe phase difference pixel PB also have different light receptionsensitivities.

Also with the structure shown in FIG. 6, a phase difference signal canbe obtained without providing a light shield film. In other words, sincethe light shield film is not provided in the phase difference pixels,the value of the pixel signal output from the phase difference pixelsdoes not become extremely smaller than that of the pixel signal outputfrom normal pixels. Therefore, in the present disclosure, there is noneed to handle the phase difference pixels as defective pixels and carryout the defect correction processing.

Further, according to the present disclosure, there is also no need tocarry out the crosstalk correction processing for removing crosstalkcomponents due to entering of light reflected by the light shield film.

FIG. 7 is a diagram showing an example of the pixel portion of the imagesensor in the case of obtaining a phase difference signal by a method ofthe related art. As shown in the figure, in the pixel portion of theimage sensor, a plurality of pixels illustrated as rectangles in thefigure are arranged in a 2D matrix.

The example of FIG. 7 shows 4 phase difference pixels in which half ofthe opening portion is optically shielded (blackened in figure). Inother words, the 4 pixel surrounded by a rectangular dotted line 71 inFIG. 7 are the phase difference pixels. Of those, a phase differencesignal in the horizontal direction is obtained by the two phasedifference pixels, and a phase difference signal in the verticaldirection is obtained by the other two phase difference pixels.

In the case of FIG. 7, since half of the opening portion of the phasedifference pixels is optically shielded, the value of the pixel signaloutput from the phase difference pixels becomes extremely smaller thanthat of the pixel signal output from normal pixels even with respect tothe pixel signals corresponding to the same light reception amount.

Therefore, in the case of FIG. 7, the phase difference pixels arehandled as defective pixels, and there is a need to carry out the defectcorrection processing of predictively generating a pixel signal of thephase difference pixels based on a pixel signal of the pixels adjacentto the phase difference pixels, for example. In this example, the defectcorrection processing needs to be carried out for the pixel signalscorresponding to the 4 phase difference pixels surrounded by therectangular dotted line 71.

Further, when the light shield film is provided as shown in FIG. 7,light is reflected by the light shield film, and the reflected lightenters the peripheral pixels.

Therefore, in the case of FIG. 7, for example, there is a need to carryout the crosstalk correction processing for removing crosstalkcomponents due to entering of light reflected by the light shield filmregarding the pixel signal output from the pixels adjacent to the phasedifference pixels. In this example, the crosstalk correction processingneeds to be carried out for the pixel signals corresponding to the twopixels adjacent to the phase difference pixels on the left-hand side ofthe figure, that are surrounded by a rectangular dotted line 72 a.Moreover, the crosstalk correction processing needs to be carried outfor the pixel signals corresponding to the two pixels adjacent to thephase difference pixels on the right-hand side of the figure, that aresurrounded by a rectangular dotted line 72 c. Similarly, the crosstalkcorrection processing needs to be carried out for the pixel signalscorresponding to the two pixels adjacent to the phase difference pixelson the upper side of the figure, that are surrounded by a rectangulardotted line 72 b and two pixels adjacent to the phase difference pixelson the lower side of the figure, that are surrounded by a rectangulardotted line 72 d.

Specifically, when obtaining a phase difference signal by the method ofthe related art, it has been necessary to carry out the defectcorrection processing for the pixel signals of the 4 pixels and thecrosstalk correction processing for the pixel signals of the 8 pixels.

In contrast, according to the present disclosure, the crosstalkcorrection processing only needs to be carried out for the 5 pixelsincluding the phase difference pixel PL, the phase difference pixel PR,the phase difference pixel PA, the phase difference pixel PB, and thepixel PC shown in FIG. 2, for example.

As described above, according to the present disclosure, it is possibleto avoid the pixel signal correction as much as possible andappropriately execute the image plane phase difference AF.

In the examples described above with reference to FIGS. 2 to 6, by notarranging the DTI exceptionally or arranging it exceptionally betweenthe phase difference pixels and the adjacent pixels in the pixel portionof the image sensor, the phase difference pixels have differentcrosstalk amounts.

However, it is also possible to provide different crosstalk amounts tothe phase difference pixels by adjusting an ion implantation amount informing an electronic barrier with respect to the pixels adjacent to thephase difference pixels in the pixel portion of the image sensor. Theelectronic barrier may be considered as one of crosstalk suppressionmechanisms for suppressing entering of charge electrons among theadjacent sensor areas.

FIG. 8 is a diagram showing an example of the cross-sectional diagram ofthe pixel portion of the image sensor to which the present disclosure isapplied. As shown in the figure, each pixel includes sensor areas 102-1to 102-4 for photoelectrically converting received light. Moreover, thesensor areas of each pixel are separated from one another by electronicbarriers 101-1 to 101-5.

For example, when the ion implantation amount in forming the electronicbarriers is small, entering of charges (electrons) from adjacent sensorareas is apt to occur, and thus crosstalk is apt to occur. In FIG. 8,for example, when the ion implantation amount in forming the electronicbarrier 101-4 is small, entering of charges (electrons) with respect tothe sensor area 102-4 when receiving light traveling from the upper leftto the lower right is apt to occur. Moreover, for example, when the ionimplantation amount in forming the electronic barrier 101-3 is small,entering of charges (electrons) with respect to the sensor area 102-2when receiving light traveling from the upper right to the lower left isapt to occur.

In this case, for example, the pixel corresponding to the sensor area102-2 and the pixel corresponding to the sensor area 102-4 can be usedas the phase difference pixels for obtaining a phase difference signalin the horizontal direction.

As described above, by adjusting the ion implantation amount in formingthe electronic barriers with respect to the pixels adjacent to the phasedifference pixels in the pixel portion of the image sensor, thecrosstalk amounts of the phase difference pixels in receiving light thathas entered from the same direction can be differentiated. Therefore,also in this case, as in the case described above with reference toFIGS. 2 to 6, it is possible to avoid the pixel signal correction asmuch as possible and appropriately execute the image plane phasedifference AF.

Further, for example, by adjusting the ion implantation amount informing the sensor areas in the pixel portion of the image sensor, thephase difference pixels can be structured to have different crosstalkamounts as in the case described above.

For example, when the ion implantation amount in forming the sensorareas is small, entering of charges (electrons) with respect to adjacentsensor areas is apt to occur, and thus crosstalk is apt to occur. InFIG. 8, for example, when the ion implantation amount in forming thesensor area 102-3 is small, entering of charges (electrons) with respectto the sensor area 102-4 when receiving light traveling from the upperleft to the lower right is apt to occur, and entering of charges(electrons) with respect to the sensor area 102-2 when receiving lighttraveling from the upper right to the lower left is apt to occur.

In this case, for example, the pixel corresponding to the sensor area102-2 and the pixel corresponding to the sensor area 102-4 can be usedas the phase difference pixels for obtaining a phase difference signalin the horizontal direction.

As described above, by adjusting the ion implantation amount in formingthe sensor areas in the pixel portion of the image sensor, the crosstalkamounts of the phase difference pixels in receiving light that hasentered from the same direction can be differentiated.

Therefore, also in this case, as in the case described above withreference to FIGS. 2 to 6, it is possible to avoid the pixel signalcorrection as much as possible and appropriately execute the image planephase difference AF.

Alternatively, by using a white CF as the CF of the pixels adjacent tothe phase difference pixels, the phase difference pixels can bestructured to have different crosstalk amounts.

FIG. 9 is a diagram showing another example of the cross-sectionaldiagram of the pixel portion of the image sensor to which the presentdisclosure is applied. As shown in the figure, each pixel includes thesensor areas 102-1 to 102-4 for photoelectrically converting receivedlight. In the example of FIG. 9, a CF 111 of the pixel corresponding tothe sensor area 102-3 is the white CF. Since the white CF is a CF havinghigh optical transparency, optical components that have passed throughthe CF 111 are apt to enter the sensor area adjacent to the sensor area102-3.

In the case of FIG. 9, entering of light with respect to the sensor area102-4 in receiving light traveling from the upper left to the lowerright is apt to occur, and entering of charges (electrons) with respectto the sensor area 102-2 in receiving light traveling from the upperright to the lower left is apt to occur.

In this case, for example, the pixel corresponding to the sensor area102-2 and the pixel corresponding to the sensor area 102-4 can be usedas the phase difference pixels for obtaining a phase difference signalin the horizontal direction.

As described above, by using the white CF as the CF of the pixelsadjacent to the phase difference pixels in the pixel portion of theimage sensor, the crosstalk amounts of the phase difference pixels inreceiving light that has entered from the same direction can bedifferentiated.

Alternatively, for example, it is also possible to structure the phasedifference pixels to have different crosstalk amounts by removing an OBBbetween the pixels adjacent to the phase difference pixels in the pixelportion of the image sensor.

FIG. 10 is a diagram showing another example of the cross-sectionaldiagram of the pixel portion of the image sensor to which the presentdisclosure is applied. As shown in the figure, each pixel includes thesensor areas 102-1 to 102-4 for photoelectrically converting receivedlight. In the example of FIG. 10, the OBB between the pixelcorresponding to the sensor area 102-2 and the pixel corresponding tothe sensor area 102-1 and the OBB between the pixel corresponding to thesensor area 102-2 and the pixel corresponding to the sensor area 102-3are removed.

With the structure as shown in FIG. 10, entering of light with respectto the sensor area 102-3 in receiving light traveling from the upperleft to the lower right is apt to occur, and entering of light withrespect to the sensor area 102-1 in receiving light traveling from theupper right to the lower left is apt to occur.

In this case, for example, the pixel corresponding to the sensor area102-1 and the pixel corresponding to the sensor area 102-3 can be usedas the phase difference pixels for obtaining a phase difference signalin the horizontal direction.

As described above, by removing the OBBs between the pixels adjacent tothe phase difference pixels in the pixel portion of the image sensor,the crosstalk amounts of the phase difference pixels in receiving lightthat has entered from the same direction can be differentiated.

Alternatively, for example, when a waveguide from the CF to the sensorarea is provided in the pixel portion of the image sensor, by removingthe waveguide of the pixels adjacent to the phase difference pixels, thephase difference pixels can be structured to have different crosstalkamounts.

FIG. 11 is a diagram showing another example of the cross-sectionaldiagram of the pixel portion of the image sensor to which the presentdisclosure is applied. As shown in the figure, each pixel includes thesensor areas 102-1 to 102-4 for photoelectrically converting receivedlight. In the example of FIG. 11, a waveguide 131-1 is provided to thepixel corresponding to the sensor area 102-1, and waveguides 131-3 and131-4 are respectively provided to the pixels corresponding to thesensor areas 102-3 and 102-4. However, a waveguide is not provided tothe pixel corresponding to the sensor area 102-2.

With the structure as shown in FIG. 11, entering of light with respectto the sensor area 102-3 in receiving light traveling from the upperleft to the lower right is apt to occur, and entering of charges(electrons) with respect to the sensor area 102-1 in receiving lighttraveling from the upper right to the lower left is apt to occur.

In this case, for example, the pixel corresponding to the sensor area102-1 and the pixel corresponding to the sensor area 102-3 can be usedas the phase difference pixels for obtaining a phase difference signalin the horizontal direction.

As described above, by removing the waveguides between the pixelsadjacent to the phase difference pixels when the waveguide from the CFto the sensor area is provided in the pixel portion of the image sensor,the crosstalk amounts of the phase difference pixels in receiving lightthat has entered from the same direction can be differentiated.

Alternatively, for example, by adjusting a light collection property ofthe OCL of the pixels adjacent to the phase difference pixels in thepixel portion of the image sensor, the phase difference pixels can bestructured to have different crosstalk amounts.

FIG. 12 is a diagram showing another example of the cross-sectionaldiagram of the pixel portion of the image sensor to which the presentdisclosure is applied. As shown in the figure, each pixel includes thesensor areas 102-1 to 102-4 for photoelectrically converting receivedlight. In the example of FIG. 12, the shape of the OCL of the pixelcorresponding to the sensor area 102-2 is plane, and thus the lightcollection property is low.

With the structure as shown in FIG. 12, entering of light with respectto the sensor area 102-3 in receiving light traveling from the upperleft to the lower right is apt to occur, and entering of charges(electrons) with respect to the sensor area 102-1 in receiving lighttraveling from the upper right to the lower left is apt to occur.

In this case, for example, the pixel corresponding to the sensor area102-1 and the pixel corresponding to the sensor area 102-3 can be usedas the phase difference pixels for obtaining a phase difference signalin the horizontal direction.

Further, the embodiments above may be used in combination. For example,the structures of the OCL, CF, and OBB can be used as the embodimentabove with reference to FIGS. 9 to 12 together with the arrangement ofthe DTI shown in FIG. 2. Moreover, for example, the structures of theOCL, CF, and OBB can be used as the embodiment above with reference toFIGS. 9 to 12 together with the arrangement of the DTI shown in FIG. 5.Furthermore, the structures of the OCL, CF, and OBB can be used as theembodiment above with reference to FIGS. 9 to 12 together with theadjustment of the ion implantation amount as described above withreference to FIG. 8.

Heretofore, the example of obtaining a phase difference signal withoutoptically shielding the opening portion of the phase difference pixelshas been descried.

However, the opening portion of the phase difference pixels may beoptically shielded so as to enable the change of the crosstalk amountsof the phase difference pixels to be detected more accurately.

FIG. 13 is a diagram showing another structural example of the pixelportion of the image sensor to which the present disclosure is applied.As shown in the figure, in the pixel portion of the image sensor, aplurality of pixels illustrated as rectangles in the figure are arrangedin a 2D matrix. Such a pixel portion is structured as a pixel array ofthe image sensor. Here, a part of the pixels arranged in the effectivearea of the pixel array are shown.

In this example, the pixels PL, PR, PA, and PB are the phase differencepixels. In other words, a lateral phase difference signal is obtained bythe phase difference pixel PL and the phase difference pixel PR, and alongitudinal phase difference signal is obtained by the phase differencepixel PA and the phase difference pixel PB.

Further, in the example of FIG. 13, the DTI is not arranged on 4 sidesof the rectangular pixel in principle, and the DTI is arrangedexceptionally on 4 sides of the pixel PC arranged at the center of the 4phase difference pixels as in the case described above with reference toFIG. 5. However, in the example of FIG. 13, the opening portion of the 4phase difference pixels is optically shielded (blackened in figure)unlike the case described above with reference to FIG. 5.

FIG. 14 is a cross-sectional diagram taken along the line A-A′ of FIG.13 for explaining a difference in the crosstalk amounts of the phasedifference pixels shown in FIG. 13.

In the case of FIG. 13, the Bayer arrangement is adopted for the pixelportion as in the case of FIG. 6, and the pixels respectively correspondto the color components of red (R), green (Gr), and blue (B). Forexample, a red CF is arranged in the phase difference pixel PL, a greenCF is arranged in the pixel PC, a red CF is arranged in the phasedifference pixel PR, and a green CF is arranged in the pixel PR1.

It is assumed that light whose direction from the upper right to thelower left becomes dominant in FIG. 14 is entering the pixel portion.

In the case of the example shown in FIG. 14, although the opticalcomponent R_(−Gr) to be incorporated from the pixel PR1 on the immediateright, that corresponds to the green color component, enters the sensorarea 52-3 of the phase difference pixel PR corresponding to the redcolor component, since the opening portion is optically shielded, theoptical component R_(−R) to be absorbed by the sensor area of the pixelitself does not enter.

Further, in the case of the example shown in FIG. 14, regarding thepixel PC corresponding to the green color component, the opticalcomponent Gr_(−Gr) to be absorbed by the sensor area 52-2 of the pixelitself and the optical component R_(−Gr) to be incorporated into thesensor area of the phase difference pixel PL on the immediate left, thatcorresponds to the red color component, enter that pixel.

However, the component R_(−Gr) is suppressed from entering by the DTI51-12 and is thus absorbed by the sensor area 52-2 of the pixel itself.

Furthermore, in the case of the example shown in FIG. 14, regarding thephase difference pixel PL corresponding to the red color component, theoptical component R_(−R) to be absorbed by the sensor area of the pixelitself does not enter since the opening portion is optically shielded.Moreover, since the DTI is provided between the phase difference pixelPL and the pixel PC, the component Gr_(−R) also does not enter thesensor area 52-1.

As a result, in the sensor area 52-1 of the phase difference pixel PL, aphotoelectric conversion is hardly performed, and the component R_(−Gr)that has been incorporated from the pixel PR1 is absorbed by the sensorarea 52-3 of the phase difference pixel PR to be photoelectricallyconverted. Consequently, when light whose direction from the upper rightto the lower left becomes dominant is entering the pixel portion, thevalue of the pixel signal output from the phase difference pixel PLbecomes small, and the value of the pixel signal output from the phasedifference pixel PR becomes large. In this case, the pixel signals ofthe phase difference pixel PL and the phase difference pixel PR areobtained mostly by crosstalk.

As described above, the opening portion of the phase difference pixelsmay be optically shielded for enabling the change of the crosstalkamounts of the phase difference pixels to be detected more accurately.

Alternatively, as in the case described above with reference to FIG. 2,it is also possible to arrange the DTI on 4 sides of the rectangularpixel in principle, not arrange the DTI exceptionally on 4 sides of thepixel PC arranged at the center of the 4 phase difference pixels, andoptically shield the opening portion of the 4 phase difference pixels.

In this case, it is effective to use a white CF for the CF of the pixelPC arranged at the center of the 4 phase difference pixels.

FIG. 15 is a diagram showing another structural example of the pixelportion of the image sensor to which the present disclosure is applied.As shown in the figure, in the pixel portion of the image sensor, aplurality of pixels illustrated as rectangles in the figure are arrangedin a 2D matrix. Such a pixel portion is structured as a pixel array ofthe image sensor. Here, a part of the pixels arranged in the effectivearea of the pixel array are shown.

In this example, the pixels PL, PR, PA, and PB are the phase differencepixels. In other words, a lateral phase difference signal is obtained bythe phase difference pixel PL and the phase difference pixel PR, and alongitudinal phase difference signal is obtained by the phase differencepixel PA and the phase difference pixel PB.

Further, in the example of FIG. 15, the DTI is arranged on 4 sides ofthe rectangular pixel in principle, and the DTI is not arrangedexceptionally on 4 sides of the pixel PC arranged at the center of the 4phase difference pixels as in the case described above with reference toFIG. 2. However, in the example of FIG. 15, the opening portion of the 4phase difference pixels is optically shielded (blackened in figure)unlike the case described above with reference to FIG. 2.

FIG. 16 is a cross-sectional diagram taken along the line A-A′ of FIG.15 for explaining a difference in the crosstalk amounts of the phasedifference pixels shown in FIG. 15.

In the case of FIG. 16, for example, a red CF is arranged in the phasedifference pixel PL, a white CF is arranged in the pixel PC, a red CF isarranged in the phase difference pixel PR, and a green CF is arranged inthe pixel PR1.

It is assumed that light whose direction from the upper right to thelower left becomes dominant in FIG. 16 is entering the pixel portion.

In the case of the example shown in FIG. 16, since the DTI 51-2 isprovided between the phase difference pixel PR corresponding to the redcolor component and the pixel PR1 on the immediate right, thatcorresponds to the green color component, the optical component R_(−Gr)does not enter the sensor area 52-3. In addition, since the openingportion is optically shielded, the optical component R_(−R) to beabsorbed by the sensor area of the pixel itself also does not enter.

Further, in the case of the example shown in FIG. 16, regarding thepixel PC corresponding to the white color component, an opticalcomponent White_(−White) to be absorbed by the sensor area 52-2 of thepixel itself and an optical component R_(−White) to be incorporated intothe sensor area of the pixel on the immediate left, that corresponds tothe red color component, enter that pixel. In this case, since the DTIis not provided between the pixel PC and the phase difference pixel PL,the optical component R_(−White) enters the sensor area 52-1 as it is.

Furthermore, in the case of the example shown in FIG. 16, since theopening portion of the phase difference pixel PL corresponding to thered color component is optically shielded, the optical component R_(−R)to be absorbed by the sensor area of the pixel itself does not enterthat pixel.

As a result, in the sensor area 52-3 of the phase difference pixel PR, aphotoelectric conversion is hardly performed, and the componentR_(−White) that has been incorporated from the pixel PC is absorbed bythe sensor area 52-1 of the phase difference pixel PL to bephotoelectrically converted. Consequently, when light whose directionfrom the upper right to the lower left becomes dominant is entering thepixel portion, the value of the pixel signal output from the phasedifference pixel PR becomes small, and the value of the pixel signaloutput from the phase difference pixel PL becomes large. In this case,the pixel signals of the phase difference pixel PL and the phasedifference pixel PR are obtained mostly by crosstalk, but since thewhite CF has high optical transparency, a difference between the valuesof the pixel signals output from the two phase difference pixels becomesmore prominent.

With such a structure, it becomes possible to detect a change in thecrosstalk amounts of the phase difference pixels more accurately, forexample.

Alternatively, an arrangement different from the Bayer arrangement maybe used for the CFs of the phase difference pixels. For example, CFs ofthe same color may be used as the CFs of the 4 phase difference pixels.For example, a green CF that has the highest optical transparency out ofred (R), green (Gr), and blue (B) may be used as the CFs of the 4 phasedifference pixels.

FIG. 17 is a diagram showing another structural example of the pixelportion of the image sensor to which the present disclosure is applied.As shown in the figure, in the pixel portion of the image sensor, aplurality of pixels illustrated as rectangles in the figure are arrangedin a 2D matrix.

In this example, the pixels PL, PR, PA, and PB are the phase differencepixels. In other words, a lateral phase difference signal is obtained bythe phase difference pixel PL and the phase difference pixel PR, and alongitudinal phase difference signal is obtained by the phase differencepixel PA and the phase difference pixel PB.

Further, in the example of FIG. 17, the DTI is arranged on 4 sides ofthe rectangular pixel in principle, and the DTI is not arrangedexceptionally on 4 sides of the pixel PC arranged at the center of the 4phase difference pixels as in the case described above with reference toFIG. 2. However, in the example of FIG. 17, the CFs of the 4 phasedifference pixels are all green CFs unlike the case described above withreference to FIG. 2.

By structuring the pixel portion of the image sensor as shown in FIG.17, the pixel signals output from the phase difference pixels constantlytake relatively-large values.

Heretofore, the example in which the 4 phase difference pixels PL, PR,PA, and PB are arranged so as to surround the center pixel PC has beendescribed. However, when such a structure is adopted, there is a need tocarry out the crosstalk correction processing for the 5 pixels asdescribed above. In other words, the crosstalk correction processingneeds to be carried out also for the pixel PC that is not the phasedifference pixel.

For example, a structure as shown in FIG. 18 may be adopted for reducingthe number of pixels to be the target of the crosstalk correctionprocessing.

FIG. 18 is a diagram showing another structural example of the pixelportion of the image sensor to which the present disclosure is applied.As shown in the figure, in the pixel portion of the image sensor, aplurality of pixels illustrated as rectangles in the figure are arrangedin a 2D matrix. Such a pixel portion is structured as a pixel array ofthe image sensor. Here, a part of the pixels arranged in the effectivearea of the pixel array are shown.

In this example, pixels PL′, PR′, PA′, and PB′ are the phase differencepixels. In other words, a lateral phase difference signal is obtained bythe phase difference pixel PL′ and the phase difference pixel PR′, and alongitudinal phase difference signal is obtained by the phase differencepixel PA′ and the phase difference pixel PB′.

Further, in the case of the structure shown in FIG. 18, while the DTI isarranged on 4 sides of the rectangular pixel in principle, the DTI isnot arranged exceptionally between the phase difference pixel PL′ andthe phase difference pixel PR′ and between the phase difference pixelPA′ and the phase difference pixel PB′.

With such as structure, when light whose direction from the upper rightto the lower left becomes dominant is entering the pixel portion, thevalue of the pixel signal output from the phase difference pixel PR′becomes small, and the value of the pixel signal output from the phasedifference pixel PL′ becomes large. This is because the crosstalk amountwith respect to the phase difference pixel PL′ becomes large. On thecontrary, when light whose direction from the upper left to the lowerright becomes dominant is entering the pixel portion, the value of thepixel signal output from the phase difference pixel PL′ becomes small,and the value of the pixel signal output from the phase difference pixelPR′ becomes large. This is because the crosstalk amount with respect tothe phase difference pixel PR′ becomes large.

Similarly, in the case of FIG. 18, since the DTI is not provided betweenthe phase difference pixel PA′ and the phase difference pixel PB′, thelight reception sensitivities of the phase difference pixel PA′ and thephase difference pixel PB′ differ.

Therefore, by adopting the structure shown in FIG. 18, a phasedifference signal can be obtained without providing a light shield film.Specifically, since the light shield film is not provided to the phasedifference pixels, the value of the pixel signal output from the phasedifference pixels does not become extremely smaller than that of thepixel signal output from normal pixels. Therefore, there is no need tohandle the phase difference pixels as defective pixels and carry out thedefect correction processing.

Moreover, there is also no need to carry out the crosstalk correctionprocessing for removing crosstalk components due to entering of lightreflected by the light shield film.

It should be noted that in the case of FIG. 18, it is desirable toarrange the CFs of the same color for the phase difference pixel PL′ andthe phase difference pixel PR′ and the CFs of the same color for thephase difference pixel PA′ and the phase difference pixel PB′ forobtaining accurate phase difference signals. For example, it isdesirable to use a green CF for the CFs of all 4 phase differencepixels.

Furthermore, in the example of FIG. 18, the 4 phase difference pixelsare arranged in an L shape and are not arranged so as to surround thecenter pixel PC as described above with reference to FIG. 2, forexample.

Therefore, when adopting the structure shown in FIG. 18, only the 4phase difference pixels can be targeted for the crosstalk correctionprocessing so that the number of pixels to be targeted for the crosstalkcorrection processing can be reduced as compared to the case of adoptingthe structures described above with reference to FIGS. 2, 5, and thelike, for example.

FIG. 19 is a system structural diagram schematically showing asolid-state image pickup apparatus to which the present disclosure isapplied. Here, a system structural diagram schematically showing astructure of a CMOS image sensor 200 to which the present disclosure isapplied is shown.

As shown in FIG. 19, the CMOS image sensor 200 includes a pixel array211 formed on a semiconductor substrate (chip) (not shown) and aperipheral circuit portion integrated on the same semiconductorsubstrate as the pixel array 211. In this example, the peripheralcircuit portion is constituted of a vertical drive circuit 212, a columnADC circuit 213, a horizontal drive circuit 214, and a system controller215.

The CMOS image sensor 200 also includes a signal processor 218 and adata storage 219. The signal processor 218 and the data storage 219 maybe realized by an external signal processor such as a DSP (DigitalSignal Processor) provided on a different substrate from the CMOS imagesensor 200 or processed by software, or may be mounted on the samesubstrate as the CMOS image sensor 200.

In the pixel array 211, pixels including a photoelectric conversiondevice (e.g., photodiode (PD)) are arranged in a 2D matrix. In otherwords, the pixel array 211 is structured by the pixel portion having thestructures of the embodiments described above with reference to FIGS. 2to 18.

Further, in the pixel array 211, a pixel drive line 216 is formed withrespect to the matrix pixel arrangement along the lateral direction ofthe figure (pixel arrangement direction in pixel row) for each row, anda vertical signal line 217 is formed along the longitudinal direction ofthe figure (pixel arrangement direction in pixel column) for eachcolumn. In FIG. 19, one pixel drive line 216 is shown, but the number isnot limited to one. One end of the pixel drive line 216 is connected toan output terminal of the vertical drive circuit 212 corresponding toeach row.

The vertical drive circuit 212 is a pixel drive circuit that isconstituted of a shift register, an address decoder, and the like anddrives the pixels of the pixel array 211 all at the same time, in a rowunit, or the like.

Signals output from the unit pixels of the pixel row selectively scannedby the vertical drive circuit 212 are supplied to the column ADC circuit213 via the vertical signal lines 217. The column ADC circuit 213carries out, for each pixel column of the pixel array 211, predeterminedsignal processing on the signals output from the unit pixels of theselected row via the vertical signal lines 217 and temporarily storesthe pixel signals subjected to the signal processing.

The horizontal drive circuit 214 is constituted of a shift register, anaddress decoder, and the like and sequentially selects a unit circuitcorresponding to the pixel column of the column ADC circuit 213. By theselective scan of the horizontal drive circuit 214, the pixel signalssubjected to the signal processing by the column ADC circuit 213 areoutput sequentially.

The system controller 215 is constituted of a timing generator thatgenerates various timing signals, and the like and performs drivecontrol of the vertical drive circuit 212, the column ADC circuit 213,the horizontal drive circuit 214, and the like based on the varioustiming signals generated by the timing generator.

The signal processor 218 carries out various types of signal processingsuch as addition processing on the pixel signals output from the columnADC circuit 213. Moreover, a logic portion is provided in the signalprocessor 218, and a signal correction circuit is provided in the logicportion.

The data storage 219 temporarily stores data requisite for the signalprocessing by the signal processor 218.

FIG. 20 is a block diagram showing a structural example of the imagepickup apparatus as an electronic apparatus to which the presentdisclosure is applied.

The image pickup apparatus 600 of FIG. 20 includes an optical unit 601constituted of a lens group, a solid-state image pickup apparatus (imagepickup device) 602, and a DSP circuit 603 as a camera signal processingcircuit. The image pickup apparatus 600 also includes a frame memory604, a display unit 605, a recording unit 606, an operation unit 607,and a power supply unit 608. The DSP circuit 603, the frame memory 604,the display unit 605, the recording unit 606, the operation unit 607,and the power supply unit 608 mutually connected via a bus line 609.

The optical unit 601 takes in incident light from an object (imagelight) and images it on an image pickup surface of the solid-state imagepickup apparatus 602. The solid-state image pickup apparatus 602converts the light amount of the incident light imaged on the imagepickup surface by the optical unit 601 into an electric signal in apixel unit and outputs it as a pixel signal. As the solid-state imagepickup apparatus 602, a solid-state image pickup apparatus such as theCMOS image sensor 200 according to the embodiment above can be used.

The display unit 605 is constituted of a panel-type display apparatussuch as a liquid crystal panel and an organic EL (Electro Luminescence)panel and displays a moving image or a still image taken by thesolid-state image pickup apparatus 602. The recording unit 606 recordsthe moving image or still image taken by the solid-state image pickupapparatus 602 onto a recording medium such as a video tape and a DVD(Digital Versatile Disc).

The operation unit 607 issues an operation instruction with respect tovarious functions of the image pickup apparatus 600 based on a useroperation. The power supply unit 608 supplies various types of power tobe operational power of the DSP circuit 603, the frame memory 604, thedisplay unit 605, the recording unit 606, and the operation unit 607 tothose supply targets as appropriate.

Further, the embodiments above have described an example of the casewhere the present disclosure is applied to a CMOS image sensor in whichunit pixels for detecting a signal charge corresponding to a visiblelight amount as a physical amount are arranged in a matrix. However, thepresent disclosure is not limited to the CMOS image sensor and is alsoapplicable to general column-type solid-state image pickup apparatusesin which a column processor is arranged for each pixel column in a pixelarray.

Moreover, the present disclosure is not limited to the solid-state imagepickup apparatus that detects a distribution of an incident light amountof visible light and images it as an image and is also applicable togeneral solid-state image pickup apparatuses (physical amountdistribution detection apparatuses) such as a solid-state image pickupapparatus that images an incident light amount distribution of infraredrays, X rays, particles, and the like as an image and, in a broad sense,a fingerprint detection sensor that detects a distribution of otherphysical amounts such as a pressure and a capacitance and images it asan image.

Furthermore, the embodiments of the present disclosure are not limitedto the embodiments above and can be variously modified without departingfrom the gist of the present disclosure.

It should be noted that the present disclosure may also take thefollowing structures.

(1) A solid-state image pickup apparatus, including

a crosstalk suppression mechanism included in each pixel arranged in apixel array, the crosstalk suppression mechanism of a part of the pixelsdiffering from that of other pixels in an effective area of the pixelarray.

(2) The solid-state image pickup apparatus according to (1) above,

in which the crosstalk suppression mechanism is a DTI.

(3) The solid-state image pickup apparatus according to (2) above, inwhich:

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF; and

the DTI around a pixel surrounded by the phase difference pixels isremoved.

(4) The solid-state image pickup apparatus according to (2) above, inwhich:

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF; and

the DTI is provided only around a pixel surrounded by the phasedifference pixels.

(5) The solid-state image pickup apparatus according to (1) above,

in which the crosstalk suppression mechanism is realized by adjusting anion implantation amount for the pixels arranged in the pixel array.

(6) The solid-state image pickup apparatus according to (5) above, inwhich:

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF; and

an ion implantation amount for an electronic barrier of a pixelsurrounded by the phase difference pixels is smaller than that for anelectronic barrier of other pixels.

(7) The solid-state image pickup apparatus according to (5) above, inwhich:

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF; and

an ion implantation amount for a sensor area of a pixel surrounded bythe phase difference pixels is smaller than that for an electronicbarrier of other pixels.

(8) The solid-state image pickup apparatus according to (1) above, inwhich:

the crosstalk suppression mechanism is an OBB;

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF; and

the OBB of a pixel surrounded by the phase difference pixels is removed.

(9) The solid-state image pickup apparatus according to (1) above, inwhich:

the crosstalk suppression mechanism is a waveguide;

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF; and

the waveguide of a pixel surrounded by the phase difference pixels isremoved.

(10) The solid-state image pickup apparatus according to (1) above, inwhich:

the crosstalk suppression mechanism is an on-chip lens;

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF; and

the on-chip lens of a pixel surrounded by the phase difference pixels isstructured such that a light collection property thereof becomes weak.

(11) The solid-state image pickup apparatus according to (1) above, inwhich:

the crosstalk suppression mechanism is realized by a color filter;

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF; and

only the color filter of a pixel surrounded by the phase differencepixels is white.

(12) The solid-state image pickup apparatus according to any one of (1)to (11) above, in which:

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF; and

the color filters of the same color are arranged for the phasedifference pixels.

(13) The solid-state image pickup apparatus according to any one of (1)to (12) above, in which:

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF; and

a pixel adjacent to a predetermined pixel in a vertical direction and apixel adjacent to the predetermined pixel in a horizontal direction outof the pixels of the pixel array arranged in a 2D matrix are the phasedifference pixels.

(14) The solid-state image pickup apparatus according to any one of (1)to (13) above, in which:

the part of the pixels in the effective area of the pixel array are aplurality of phase difference pixels for obtaining a phase differencesignal used in an image plane phase difference AF;

two pixels adjacent to each other in a vertical direction and two pixelsadjacent to each other in a horizontal direction out of the pixels ofthe pixel array arranged in a 2D matrix are the phase difference pixels;and

the two pixels adjacent to each other in the vertical direction and thetwo pixels adjacent to each other in the horizontal direction arearranged in an L shape.

(15) An electronic apparatus, including

a solid-state image pickup apparatus including a crosstalk suppressionmechanism included in each pixel arranged in a pixel array, thecrosstalk suppression mechanism of a part of the pixels differing fromthat of other pixels in an effective area of the pixel array.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. An imaging device, comprising: a first and asecond photoelectric conversion regions arranged in a first row; a thirdand a fourth photoelectric conversion regions arranged in a second row;a fifth and a sixth photoelectric conversion regions arranged in a thirdrow; and a deep trench isolation (DTI) structure, wherein, the thirdphotoelectric conversion region is arranged between the first and thefifth photoelectric conversion regions along a column direction, thefourth photoelectric conversion region is arranged between the secondand the sixth photoelectric conversion regions along the columndirection, a first part of the DTI structure is disposed between thefirst and the second photoelectric conversion region, a second part ofthe DTI structure is disposed between the first and the thirdphotoelectric conversion region, a third part of the DTI structure isdisposed between the second and the fourth photoelectric conversionregion, a fourth part of the DTI structure is disposed between the fifthand the sixth photoelectric conversion region, a fifth part of the DTIstructure is disposed between the third and the fifth photoelectricconversion region, a sixth part of the DTI structure is disposed betweenthe fourth and the sixth photoelectric conversion region, and a part ofthe DTI structure is not disposed between the third and the fourthphotoelectric conversion region.
 2. The imaging device according to theclaim 1, wherein: the first and the second photoelectric conversionregions are separated by an electronic barrier, and the first part ofthe DTI structure is located within the electronic barrier.
 3. Theimaging device according to the claim 1, wherein each of the third andthe fourth photoelectric conversion regions is configured to generate asignal that can be used to obtain a phase difference signal used in animage plane phase difference auto focus.